<template>
  <div class="chat-box">
    <header>聊天室 (在线:{{count}}人)</header>
    <div class="msg-box" ref="msg-box">
      <div
          v-for="(i,index) in list"
          :key="index"
          class="msg"
          :style="i.userId == userId?'flex-direction:row-reverse':''"
      >
      </div>
    </div>
    <div class="input-box">
      <input type="text" ref="sendMsg" v-model="contentText" @keyup.enter="sendText()" />
      <div class="btn" :class="{['btn-active']:contentText}" @click="sendText()">发送</div>
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      ws: null,
      count: 0,
      userId: this.$store.getters.id, // 当前用户ID
      username: this.$store.getters.name, // 当前用户昵称
      avatar: this.$store.getters.avatar, // 当前用户头像
      list: [], // 聊天记录的数组
      contentText: "" // input输入的值
    };
  },
  mounted() {
    this.initWebSocket();
  },
  destroyed() {
    // 离开页面时关闭websocket连接
    this.ws.onclose(undefined);
  },
  methods: {
    // 发送聊天信息
    sendText() {
      let _this = this;
      _this.$refs["sendMsg"].focus();
      if (!_this.contentText) {
        return;
      }
      let params = {
        userId: _this.userId,
        username: _this.username,
        avatar: _this.avatar,
        msg: _this.contentText,
        count: _this.count
      };
      _this.ws.send(JSON.stringify(params)); //调用WebSocket send()发送信息的方法
      _this.contentText = "";
      setTimeout(() => {
        _this.scrollBottm();
      }, 500);
    },
    // 进入页面创建websocket连接
    initWebSocket() {
      let _this = this;
      // 判断页面有没有存在websocket连接
      if (window.WebSocket) {
        let serverHot =  window.location.hostname;
        let sip = '房间号'
        // 填写本地IP地址 此处的 :9101端口号 要与后端配置的一致！
        var url = `ws://${serverHot}:8089/chat/`; // `ws://127.0.0.1/9101/groupChat/10086/聊天室`
        let ws = new WebSocket(url);
        _this.ws = ws;
        ws.onopen = function(e) {
          console.log("服务器连接成功: " + url);
        };
        ws.onclose = function(e) {
          console.log("服务器连接关闭: " + url);
        };
        ws.onerror = function() {
          console.log("服务器连接出错: " + url);
        };
        ws.onmessage = function(e) {
          //接收服务器返回的数据
          let resData = JSON.parse(e.data)
          _this.count = resData.count;
          _this.list = [
            ..._this.list,
            { userId: resData.userId, username: resData.username, avatar: resData.avatar, content: resData.msg }
          ];
        };
      }
    },
    // 滚动条到底部
    scrollBottm() {
      let el = this.$refs["msg-box"];
      el.scrollTop = el.scrollHeight;
    }
  }
};
</script>

<style lang="scss" scoped>
.chat-box {
  margin: 0 auto;
  background: #fafafa;
  position: absolute;
  height: 100%;
  width: 100%;
  max-width: 700px;
  header {
    position: fixed;
    width: 100%;
    height: 3rem;
    background: #409eff;
    max-width: 700px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-weight: bold;
    color: white;
    font-size: 1rem;
  }
  .msg-box {
    position: absolute;
    height: calc(100% - 6.5rem);
    width: 100%;
    margin-top: 3rem;
    overflow-y: scroll;
    .msg {
      width: 95%;
      min-height: 2.5rem;
      margin: 1rem 0.5rem;
      position: relative;
      display: flex;
      justify-content: flex-start !important;
      .user-head {
        min-width: 2.5rem;
        width: 20%;
        width: 2.5rem;
        height: 2.5rem;
        border-radius: 50%;
        background: #f1f1f1;
        display: flex;
        justify-content: center;
        align-items: center;
        .head {
          width: 1.2rem;
          height: 1.2rem;
        }
        // position: absolute;
      }
      .user-msg {
        width: 80%;
        // position: absolute;
        word-break: break-all;
        position: relative;
        z-index: 5;
        span {
          display: inline-block;
          padding: 0.5rem 0.7rem;
          border-radius: 0.5rem;
          margin-top: 0.2rem;
          font-size: 0.88rem;
        }
        .left {
          background: white;
          animation: toLeft 0.5s ease both 1;
        }
        .right {
          background: #53a8ff;
          color: white;
          animation: toright 0.5s ease both 1;
        }
        @keyframes toLeft {
          0% {
            opacity: 0;
            transform: translateX(-10px);
          }
          100% {
            opacity: 1;
            transform: translateX(0px);
          }
        }
        @keyframes toright {
          0% {
            opacity: 0;
            transform: translateX(10px);
          }
          100% {
            opacity: 1;
            transform: translateX(0px);
          }
        }
      }
    }
  }
  .input-box {
    padding: 0 0.5rem;
    position: absolute;
    bottom: 0;
    width: 100%;
    height: 3.5rem;
    background: #fafafa;
    box-shadow: 0 0 5px #ccc;
    display: flex;
    justify-content: space-between;
    align-items: center;
    input {
      height: 2.3rem;
      display: inline-block;
      width: 100%;
      padding: 0.5rem;
      border: none;
      border-radius: 0.2rem;
      font-size: 0.88rem;
    }
    .btn {
      height: 2.3rem;
      min-width: 4rem;
      background: #e0e0e0;
      padding: 0.5rem;
      font-size: 0.88rem;
      color: white;
      text-align: center;
      border-radius: 0.2rem;
      margin-left: 0.5rem;
      transition: 0.5s;
    }
    .btn-active {
      background: #409eff;
    }
  }
}
</style>
